Placer mining machine



Dec. 15, 1931: DUGAN v 1,836,366

PLACER MINING MACHINE Filed April 10, 1930 swam tow v v $52 I v Patented Dec. 15, 1931' is '1' Q UNIT D- er Ares 'oFFifcE THOMAS mean, cesarean cononiino} Assienon meemeum sla FRED i; i (ANTHONY AND JOHN nfrrnnEN DoNE-nierrrn IQ R. BENJAMIN nAvIs, ALL or Fig. 2 is a section through box, takenon line 55,"Fig. 3., l

s QIWIG'HI'I'AA, Kansas Application filed ep'rnio,

Thisinvention relates to improvementsin placer min'ing machines of the type employed for removing goldand other valuable metals from sand or gravel.

It is the object of thisinvent-ion to produce a power operated placer mining machine. of. such design and construction that it can be operated by onemanand which shall be providedwith means for separating the light or:-

flour gold from the-heavier articles {while the material is in a drystate; 1 V 1 The above and other obects which-maybe-a come apparent as this description proceeds are attained bymeans of a construction and arrangement of parts that will now-be described in detail, and for this purpose reference will be had to the accompanying drawings in" which the preferred embodiment of. the invention" has been illustrated; and in which: improved placer-mining machine;- 7 V 1' the separator that is employed in connection with'the ma-f chine} i r Fig. 3 is a side elevation partly in'section, showing. the sluiceboxes; 1. t 1' .Fig. 4 is atop plan view of a portionuof one of the sluice boxes; and a Fig. 5 is a transverse section-of a ."sluice In. the drawings numer'alrl represents the surface of the ground that is to be worked, and-2 represents in ageneral way the truck that has one end'supported'on wheels 3 and v the vothersupported on a tracklaying traction assembly 4 of the type employed in con-s nection withithat type of tractor usually designated ascaterpillar 1 tractor. Supported on the truck is an internal combustionengine 5 that has merely been indicated in a diagrammatic manners This'engine' serves to producepower for. operating the machine, as well as for transporting it when it ismovedu: Secured to, the front end of'the truck is a boom 6 that has one-end pivoted so rneonit amme lc e I p 193d. 7 ser al no. 443,208.

. theiunder surface thereo f moves upw in s thed-irection ofthearrowi The buckets of the conveyor carry sandand gravel upward-x ly anddepos1t the ,sameion a transverse conveyorzlO: that in} turn deposits the material ina 'hopper 11 having a spout that projects so. as to convey the coarsematerial to one side.

Located underneath the hopper 13is asepainto the upper'end of arotating screen cyl inder. 1-2; Located underneath this cylinder;

rator" comprising a casing having a top wall 15 and side walls16.. At one :end of this casing Lhave located a blower. 17 within which ismounted afan having blades 18. This fan is rotated :in a clockwise direction and delivers a strong: breeze through the nozzle 19; .A pluralitypf screens, of which three sections A, Band Ghavebeen shown, are supported fromthe sides 16'by means of links 20. The upper ends oftheselinks are pivotally'connected with the sides and the a screenbottom 22' which may be thesame mesh for' all of the screens if desired. connectingflrodl 23; has one. end. connected with abracketQt on the under surface of screen section B andthe other connected with aneccentric. 25 on the shaft 26 of thefanv f The.

several screen sections are interconnected by means or links 27 so that they will reciprocate lower ends with the side members .21 of the 3 screen frames. Eaclrframe is provided with" as a unit. When the fan is: rotating the? screens will reciprocate and material will.

pass from 'thedischarge openingof hopper 13v outwardly over the screens and be discharged therefrom at end 27. Located beneath the screens are four screw conveyors 28,29, 30

and 31. Extending upwardly from the cas ings surrounding the screw conveyors28', 29 and 30 areinclined partitions 32, 33 and 34 respectively. The upper end of partition 34 is'connected with the casing surrounding the conveyor 31:, while the otherpartitions terminate above the next outwardly located con veyors. When the fan is operating material will pass throughthe screensand as this falls through the strong air current-that is pro;

' duced by thetan the lighter'materials will be carried outwardly, while the heavier materials will pass through the air currents and onto the partitions 32, 33 and 34. The very light materials, such as flour gold will be carried along until it reaches the end conveyor 3i where it will. be intercepted by the end wall 35 and accumulate about the conveyor which as it rotates moves the material outwardly towards one side. From one or all of the conveyors 28, 29 and 30, values can be obtained, and itis therefore desirable to pass the materails that accumulate in these conveyors through a sluice box where the metallic. values can be separated in the usual manner. Since the space available for the sluice boxes is limited, they have been made of several short sections and in the drawings a three-part sluice box has been illustrated. The upper, intermediate and lower sluice box sections have been designated respectively by reference numerals 36, 37 and 38. For the purpose of supporting these boxes, vertical beams 39 have been provided. There is one beam on each side of the sluice boxes at each end thereof and the sluice boxes are supported from these beams by means comprising shafts 40.

and links 41. The higher end of the section 36 is connected with the lower end of section 37 by means of links 41 that have their upper ends pivotally connected with sluice box section 36 and their lower ends with sluice box section 37 and the upper end of sluice box section 37 is similarly connected with the lower end of sluice box section 38. Secured to the frame member 42 isa shaft 43 that is provided at one end with a belt wheel 44 with which the belt 45 cooperates. This belt has its upper end associated with a pulley on the end of the fan shaft 26 and when the fan rotates, the sluice boxes will be reciprocated. I find that the best results are obtained when the sluice boxes have a sidewise motion as well as a longitudinal motion and in order to obtain movement simultaneously in two directions, I have secured to one of the supporting beams 39 a bracket 46 that has a portion inclined towards the sluice box and the latter is provided with a block 47 that contacts with the inclined inner surface of the bracket and therefore the sluice box is given a transverse movement as well as a longitudinal movement, when it is reciprocated. Shaft 43 is provided with an eccentric 48 and a connecting rod 49 has one end connected with the eccentric and the other pivotally connected at 5-0 to the upper end of section 36, and therefore when the fan is rotated, the sluice boxes will be reciprocated and will also move transversely and since they are supported on links 20, they will also have movement in an arc and these three movements give to the sluice boxes a motion that corresponds quite closely to'the motion that a miner gives to a pan when panning gold. In order to facilitate the cleaning up of the sluice boxes the latter have been provided with removable pans 51 that are formed from short sections and the bottoms of these pans may be provided with cleats 52 as illustrated or they may have a covering of carpet or wires or some of them may even be formed by amalgamated copper plates. \Vhen the sluice boxes are to be cleaned the pans are removed and replaced by others, and therefore it is not necessary to close down the machine for any considerable length of time because the pans can be quickly removed and replaced.

The water for the separation that takes place in the sluice boxes is supplied through a pipe 51a like that shown in Fig. 2. This pipe may be connected with a pump or with any source from which water can be obtained.

Since this machine is power operated and digs and elevates the sand and gravel, it is possible for one man to operate the entire machine and therefore the cost of handling a ton of material is greatly decreased.

Since the flour gold and other light metallio particles are carried along by the air currents and deposited in the housing of screw conveyor 31, the materials that are delivered by this conveyor are usually rich in gold values, and since the material in this conveyor is very light, it is not suitable for treatment in the sluice boxes.

The parts are so arranged that either or all of the conveyors, 28, 29 and 30, can be connected with the sluice boxes so that all of the values can be removed from the sand and gravel.

In some cases it is unnecessary to separate the materials by means of the air separator and when this is found to be the case, the latter can be removed and the material from hopper 13 can be discharged directly into the sluice boxes.

, Where the sand and gravel contains considerable quantities of flour gold the air sep arator shown and described is quite necessary for the best results as flour gold is so light that it will float on water and will therefore be lost if it is introduced with other material into the sluice boxes.

From the above description it will be seen that I have produced a mining machine that is self-contained and power operated, and which can beoperated by one man if necessary. This machine is mounted on a truck that will travel by its own power and can therefore be readily transported from one place to another and by virtue of its air separator, it is possible to save a large percentage of the flour gold and other fine values that would otherwise be lost.

I-Iaving described the invention what I claim as new is:

A placer mining machine for separating metallic particles from nonmetallic material containing the same comprising, in combination, a frame, a screen carried thereby,

means for delivering material to the screen, a hopper located beneath the screen and adapted to receive the screenings, a separator located beneath the hopper, the sepa-- rator comprising a sectional screen, means 7 comprising links for suspending the screen,

means for reciprocating the screen, means'for directing an air current along the bottom of the screen whereby any material passing through the screen Will be separated in accordance with its Weight, a plurality of transversely extending conveyors located underneath the screen, inclined bottoms for direct ing materials to the conveyors, a sluice'box located underneath the transverse conveyors,

and means for reciprocating the sluice boxes and for imparting to them a transverse movement.

In testimony whereof I aflix my signature.

THOMAS DUGAN. 

